syzbot

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BUG: KCSAN: data-race in __jbd2_journal_temp_unlink_buffer / jbd2_journal_dirty_metadata

write to 0xffff8881075d0c50 of 4 bytes by task 10267 on cpu 1:
 __jbd2_journal_temp_unlink_buffer+0x1d6/0x290 fs/jbd2/transaction.c:2017
 __jbd2_journal_file_buffer+0x175/0x380 fs/jbd2/transaction.c:2515
 jbd2_journal_dirty_metadata+0x423/0x670 fs/jbd2/transaction.c:1587
 __ext4_handle_dirty_metadata+0xc6/0x590 fs/ext4/ext4_jbd2.c:331
 ext4_do_update_inode fs/ext4/inode.c:5141 [inline]
 ext4_mark_iloc_dirty+0x12f2/0x16f0 fs/ext4/inode.c:5724
 __ext4_mark_inode_dirty+0x4db/0x5e0 fs/ext4/inode.c:5918
 ext4_dirty_inode+0x86/0xa0 fs/ext4/inode.c:5947
 __mark_inode_dirty+0x72/0x6f0 fs/fs-writeback.c:2274
 generic_update_time fs/inode.c:1766 [inline]
 update_time fs/inode.c:1779 [inline]
 file_update_time+0x3a4/0x3e0 fs/inode.c:1995
 file_modified+0x62/0x80 fs/inode.c:2018
 ext4_write_checks fs/ext4/file.c:247 [inline]
 ext4_buffered_write_iter+0x1f9/0x3e0 fs/ext4/file.c:264
 ext4_file_write_iter+0x48a/0x10b0 fs/ext4/file.c:502
 call_write_iter include/linux/fs.h:1977 [inline]
 do_iter_readv_writev+0x2cb/0x360 fs/read_write.c:740
 do_iter_write+0x112/0x4c0 fs/read_write.c:866
 vfs_iter_write+0x4c/0x70 fs/read_write.c:907
 iter_file_splice_write+0x40a/0x750 fs/splice.c:689
 do_splice_from fs/splice.c:767 [inline]
 direct_splice_actor+0x80/0xa0 fs/splice.c:936
 splice_direct_to_actor+0x345/0x650 fs/splice.c:891
 do_splice_direct+0xf5/0x170 fs/splice.c:979
 do_sendfile+0x7a6/0xe20 fs/read_write.c:1260
 __do_sys_sendfile64 fs/read_write.c:1319 [inline]
 __se_sys_sendfile64 fs/read_write.c:1311 [inline]
 __x64_sys_sendfile64+0xa9/0x130 fs/read_write.c:1311
 do_syscall_64+0x39/0x80 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xae

read to 0xffff8881075d0c50 of 4 bytes by task 10271 on cpu 0:
 jbd2_journal_dirty_metadata+0x1dd/0x670 fs/jbd2/transaction.c:1487
 __ext4_handle_dirty_metadata+0xc6/0x590 fs/ext4/ext4_jbd2.c:331
 ext4_do_update_inode fs/ext4/inode.c:5141 [inline]
 ext4_mark_iloc_dirty+0x12f2/0x16f0 fs/ext4/inode.c:5724
 __ext4_mark_inode_dirty+0x4db/0x5e0 fs/ext4/inode.c:5918
 ext4_dirty_inode+0x86/0xa0 fs/ext4/inode.c:5947
 __mark_inode_dirty+0x72/0x6f0 fs/fs-writeback.c:2274
 generic_update_time fs/inode.c:1766 [inline]
 update_time fs/inode.c:1779 [inline]
 file_update_time+0x3a4/0x3e0 fs/inode.c:1995
 file_modified+0x62/0x80 fs/inode.c:2018
 ext4_write_checks fs/ext4/file.c:247 [inline]
 ext4_buffered_write_iter+0x1f9/0x3e0 fs/ext4/file.c:264
 ext4_file_write_iter+0x48a/0x10b0 fs/ext4/file.c:502
 call_write_iter include/linux/fs.h:1977 [inline]
 do_iter_readv_writev+0x2cb/0x360 fs/read_write.c:740
 do_iter_write+0x112/0x4c0 fs/read_write.c:866
 vfs_iter_write+0x4c/0x70 fs/read_write.c:907
 iter_file_splice_write+0x40a/0x750 fs/splice.c:689
 do_splice_from fs/splice.c:767 [inline]
 direct_splice_actor+0x80/0xa0 fs/splice.c:936
 splice_direct_to_actor+0x345/0x650 fs/splice.c:891
 do_splice_direct+0xf5/0x170 fs/splice.c:979
 do_sendfile+0x7a6/0xe20 fs/read_write.c:1260
 __do_sys_sendfile64 fs/read_write.c:1319 [inline]
 __se_sys_sendfile64 fs/read_write.c:1311 [inline]
 __x64_sys_sendfile64+0xa9/0x130 fs/read_write.c:1311
 do_syscall_64+0x39/0x80 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xae

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 10271 Comm: syz-executor.0 Not tainted 5.12.0-rc2-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
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